What is the rock material called that has filled in the vent of a volcano and hardened?
I learned about this when I was in the seventh grade. Pumice is volcanic. It was made by nature when lava and gases was thrown out of a volcano. As the gas bubbles escaped from the lava, it become frothy. When the lava cooled and hardened, the result was a very light rock material filled with tiny bubbles of gas.
The space between cells can be called the extracellular space, the extracellular material, or the extracellular matrix. This space is not a vacuum; it is filled with material. If the material is gel-like it is called the ground substance, which is filled with many dissolved solute particles, and the tissue will be loose. If the material in the extracellular space has some fibers of protein in it, the entire tissue will have a stronger consistency.
The volcano is destructive by the magma inside it. The substance called "rhyolite" or "sticky magma" that is filled has so much gas in it, it pushes up. Because the magma is sticky, the lava gets harder and harder to push up and basically turns into an explosive volcano. The magma seeps through towns, destroying buildings and killing people.